Suction cleaner



June 3, 1941'- c. H. 'TAYLOR SUC TION CLEANER Filed May 9, 1938 3Sheets-Sheet l INVENTOR Charles H T a ylor ATTORNEY 4 SUCTION CLEANERFiled y 1938 s Sheets-Sheet 2' 8 INVENTOR Charles H Taylor ATTORNEY June3, 1941..

3 Sheets-Sheet 5 3. H. TAYLOR SUCTION CLEANER Filed May 9, 1938/IIIIIIIIIIIIIl/IIIIII III/Illa), VIII/I/l/I/II/l INVENTOR Charles]?!Tayiar A A N. 'llw M a v.

unnn'nwAnAnJmlAill ATTORNEY Patented June 3, 1941 SUCTION CLEANERCharles H. Taylor, Springfield, Mass, assignor to The Hoover Company,

corporation of Ohio North Canton, Ohio, at

Application May 9, 1938, Serial No. 206,739 3 Claims. in. 15-16) Thisinvention relates to improvements in suction cleaners and moreparticularly to means whereby the nozzle of a suction cleaner isautomaticallymaintained at the correct'height above the surface of thefloor covering to be cleaned regardless of its quality, texture or othercharacteristics. I

Heretofore, it has been the standard practice to equip suction cleanerswith some form of manually operated mechanism or device for adjustingthe height of the nozzle for different grades and texture of carpet, itbeing well known that a predetermined uniform spacing of the nozzleabove the carpet surface is essential to efficient operation andeffective cleaning and further, that the nozzle should be raised orlowered to compensate for varying depths to which the wheels sink intocarpets having different pile thickness. The chief objection to thesemanually operated adjusting devices is the fact that it is usuallydifficult for the operator to make the correct adjustment, not beingfamiliar with the operating conditions. Moreover, operators frequentlyneglect to make any adjustment at all and as a consequence, thecompensation for variations in carpet conditions is at best, uncertainand haphazard.

Therefore, the principal object of the invention is to incorporate anozzle adjusting device into a suction cleaner that will automaticallyadjust itself to the particular kind or texture of carpet .to be cleanedand thus eliminate the necessity of relying upon the operator to performany act other than placing the cleaner upon the floor covering andoperating it in the usual manner.

And a further-object of the present invention is to provide a type ofautomatic nozzle height adjusting or regulating mechanism consisting ofdual wheels vertically adjustable against spring tension to support theload, and so interconnected that the displacement ofone wheel in contactwith the carpet surface adjusts the other wheel, which in turndetermines the correct height of the nozzle.

With the foregoing introductory matter, the invention will now be 'morefully disclosed in connection with the accompanying drawings in which: v

Figure 1 is a geenral view in side elevation of a suction cleanerembodying the features of the invention and shown under operatingconditions on a carpet ofmedium thickness.

Figure 2 is a fragmentary bottomplan view of the cleaner showing one setof adjustable wheels.

Figure 3is a fragmentary view of the adjusting mechanism set foroperating on a relatively thick carpet and shown in side elevation astaken on line 33 of Figure 2.

Figure 4 is an enlarged detail view in vertical cross section taken online 44 of Figure 1.

Figure 5 is a perspective view of the adjusting mechanism assembly. iFigure 6 is a perspective view of the bell crank lever forming a part ofthe adjusting mechanism.

Figure 7 is a view in side elevation of a modified nozzle heightadjusting mechanism; and

neuvered cleaner adapted for household use and consisting generally of acasing I mounted on wheels and provided with a nozzle portion 2extending transversely at itsforward end. The casing I includes a fanchamber 3 in which is mounted a suction fan driven by a motor enclosedwithin a dome-like hood 4 on the casing. The nozzle portion of thecasing consists-primarily of a downwardly opening nozzle chambercommunicating with the fan chamber through a suitable inlet passage,said fan chamber communicating with a dirt bag 5 having detachableconnection with anlexhaust outlet connection at the rear end of thecasing I. A handle completes the cleaner assembly, the lower end portionin the form of a U-shaped bail 6 being pivotally connected to bracketsI, on opposite-sides of the casing I. 1 Otherwise, the cleaner embodiesthe usual features of design which need not be described in detail.

The cleaner casing is supported upon wheels positioned near the frontand rear ends thereof, the rear wheels 8, 8 being of standard size anddimensions and are journalled upon a suitable bracket 9 fixed to thecleaner casing. These wheels function in the usual manner to support therear portion of the cleaner and will not be further considered.

The front wheels however, consist of two sets or pairs arranged side byside and substantially in axial alignment with each other, and arecapable of adjusting themselvesautomatically under operating loads andin a degree determined by the characteristics of the carpet cleaner isbeing operated.

Referring in greater detail to the front wheel arrangement, thecorresponding wheels of each pair are-located immediately to the rear ofthe outer end portions of the nozzle chamber and on which thecasing andmay be further distinguished by the fact that they are substantiallywider than. the secondary or auxiliary wheels II, II which arepositioned just inwardly from and in close proximity to the supportingwheels. For the purpose of the present discussion the primary supportingwheels I may be assumed to be about three times the width of the narrowauxiliary wheels II, which have a width of say one-quarter A) of aninch.

The supporting wheels HI, ID are journalied at the forward ends ofpivoted supporting brackets I2, 'I2 preferably assembled from sheetmetal parts and pivotally supported, with corresponding brackets I3, I3for the auxiliary wheels II, II, upon frames I4, I4 fixed to theunderside of the cleaner casing. Each of the wheel supporting frames I l(Figure 5) isstamped from sheet metal with ears Ida, Isa at each endwhich bear against depending bosses I5, I5 integral with the undersideof the cleaner casing and to which the frame is fixed by means of screwsto assume an inclined position at an angle of about 45. The main portionof each frame I I consists of a vertical central web It roughlytriangular in shape with marginal segments 'on opposite sides thereoffor supporting the several parts of the wheel assembyl. Thus, at theupper end of the frame is a downwardly projecting integral arm I!supporting between its lower end and that of the web I6, a bearing pinI8 on'which bushing or collar I9 is mounted. This bushing I9, preferablyflanged at either end, forms the bearing for the supporting wheelbracket I2, having the general shape of a bell crank lever (Figure 6)and consisting of a pair of L-shaped plates 20, 20, spaced apart withtheir horizontal arms a, 20a extending forwardly and supporting the endsof the journal pin I0a for the front wheel III. The other and verticalarms 20b, 20b of the plates 20, 20 are bent at right angles just abovethe bushing I9 and laterally inward and again bent upwardly at rightangles and into contact with each other and finally joined together intoa single upright lever arm offset some distance inwardly from the planeof the wheel l0 supported by the main portion of the bracket with theextremity of one of the upright arms fashioned into a ta pered orwedge-shaped cam 2| extending rearwardly with a slight inclination in anupwardly direction, the under edge of this cam being the active camsurface, and inclined to the vertical at an angle of approximately 45.

To complete the pivotal mounting of each supportin wheel bracket I2 onthe supporting frame It a torsion spring 22 consisting of approximatelythree turns is coiled about the bushing I9, one end of the torsionspring being hooked about the rear edge of the wheel supporting bracketI2 immediately above the bearingl9 (Figure 4) and the other extremity ofthe springbeing caught over a finger 23 formed integral with theoutlying 1 arm II of the frame I4 (Figure 5), the torsion spring thusacting to exert continuous pressure on the wheel supporting bracket I2in a direction to yieldingly resist the load placed upon the supportingwheels Ill, II] when the cleaner is in operation. In other words, eachtorsion spring 22,

' tends to rotate its wheel supportingbr acket I2 in a clockwisedirection as viewed in Figurel. However, it is to be noted at this pointthat the tension exerted by the torsion springs 22 is calculated to beconsiderably less than that necessary to overcome the operating load onthe front wheels, although ample to support the-front portion of thecleaner under static load conditions, that is, when the cleaner is notoperating under suction load, as will presently be explained in greaterdetail.

In the meantime, it may be observed that the rotative movement of thewheel carrying brackets I2, I2 on their bearings I9, I9 is transmittedfrom each associated auxiliary wheel carrying brackets I3 through themedium of a Z-shaped cam lever 24 pivotally mounted on a bearing pin 25carried on the frame It directly to the rear of the pivotal axis of thewheel supporting bracket I2 and projecting inwardly beyond the centralweb I6 of the frame.

Leaving the Z-shaped cam lever 24 for the moment, the supporting bracketI3 for each of the auxiliary wheels II i located just inwardly from theprimary wheel supporting bracket I2 and consists of an elongatedU-shaped lever formed of sheet metal and having bearing at its rear endupon a transverse pivot pin 26 supported at the rear end of the frameI4; This wheel supporting lever I3 extends in a horizontal direction andthroughout its forward end portion it is bifurcated to receive thenarrow auxiliary or pilot wheel II. As clearly shown in Figures 2 and 4,each lever I3 has an upwardly opening U-shaped portion 21 with a sectionof its outermost side Wall cut away as at 21a to allow the pivot pin 25to project into the'open U-shaped recess and to bring the Z-shaped camlever 24, previously identified, into position immediately above thelever.

Now, the cam lever 24 carries at its lower end and just forwardly of itspivotal support on the pin 25, a roller 28 which bears upon a narrowmetal plate or strip 29 extending along the bottom of the U-shapedrecess intermediate the ends of each lever I3, said strip being suitablyanchored as by welding at its rearmost end. Im-

mediately beneath the forward and free end of the strip 29 is anadjusting screw 30 threaded through the bottom web of the lever I3 andbearing at its upper end against the underside of the plate 30 which,being somewhat resilient, is adapted to be raised or lowered thereby toimpart a limited adjustable rotative movement to the Z-shapedcam lever24 by contact with the roller 28. The adjusting screw 30 is providedwith a lock nut 3i to hold the same in any position of adjustment. Thepurpose of this adjusting screw will' be brought out in connection withthe discussion of the operation of the nozzle adjusting mechanism.

As thus .far described, each Z-shaped cam lever 24 pivots aboutits-bearing pin.25, the

mation of the cam lever 24, a short arm 24a projects rearwardly from itsupper end with its extremity bent at right angles and folded back uponitself to form an abutment for one end of a compression spring 33. Theopposite end of downwardly by said spring is supported at the end of atension adjusting screw 34 supported by an ear 35 formed integral withthe supporting bracket l4 and extending transversely from the rear edgeof the central web |6 thereof (Figure A lock nut 36 is applied to theouter portion of the adjusting screw 34 which also has its end slottedtransversely so that a screw driver may be applied for rotating toeither increase or decrease the pressure exerted by the coil spring 33on the Z-shaped cam lever 24.

'I'his completes the description of each adjustable front wheel assemblyand, bearing in mind that the same is duplicated on each side of thecleanenthe adjusting action may be suinmarized as follows: The outermostor wide supporting wheels l0, l0 are adjusted upwardly and the rockingmovementof their supporting brackets l2, l2 limited however to themovement thereto through the contact of Y the cam rollers 32, 32 withthe cams 2|, 2| which in turn depends upon the degree of rocking oroscillating movement imparted to the Z-shaped cam levers 24, 24 by themovement of the sup porting brackets l3, or narrow auxiliary wheels H,It follows therefore that if the auxiliary wheels are permitted to bedepressed below their normalhorizontal position, this movement allowsthe cam levers 24, 24 to rock forwardly under the tension of the springs33, 33 and transmit a rocking movement to the main wheel supportingbrackets l2, l2, in the same direction, that is, downwardly in aclockwise direction, with the result that the primary load supportingwheels l0, ID are depressed and the forward end of the cleaner body iselevated to raise the nozzle accordingly.

And in this-connection, it is important to note that the auxiliarywheels I II are journalled at the ends of lever arms considerably longerthan the lever arms a of the brackets l2, I2 carrying the supportingwheels Ill, Ill, and hence, the force exerted by the springs actingthrough the former is greater than that acting through the latter withthe result that the auxiliary wheels II are depressed with greater forceand therefore assume a greater part of the load,

say, from 75 to 80% with the main supporting wheels l0, l0 carrying theremaining or 20% of the load. However, this applies only to the staticload, so that upon starting the cleaner in operation, the suction loadbecomes effective and immediately there is a tendency for the wheels tosink or penetrate to a greater depth into the carpet 'nap. Now, sincetheauxiliary wheels II are capable of carrying the greater l3 carryingthe innermost nalled at the end of alonger lever load before yielding tothe added weight imposed upon them, it follows that they will sink intothe carpet nap to the maximum depth permitted by the thickness andtexture of the carpet pile andwhen that depth is reached, the auxiliarywheels will move toward the cleaner casing and the movement of thesupporting levers |3, |3 will be transmitted to the brackets 2, l2

carrying the main supporting wheels I, I0,

through the cam levers 24, 24. And since the main supporting wheels l0,ID are intended pri marily to carry only the suction load and to rideupon the carpet nap with little penetration, due to their relativelywider tread surfaces, their vertical position determines the ultimateheight of the nozzle above the carpet surface. In short, the wide wheelsl0, I0

" are displaced vertically and move upwardly or downwardly with theauxiliary wheels II but in a reduced amount proportional to therelacomparatively '7 tive lengths of their respective-lever arms. Thusit will be seen that the carpet pile, the greater the penetration of theauxiliary wheels II and the correspondingly greater vertical adjustmentof the supporting wheels l0, ID in a direction to raise or lower thenozzle and thus maintain its uniform height regardless of the particularcharacteristics of the carpet being cleaned.

However, before starting the cleaner in operation, the adjustingmechanism has to be properly set by manipulating either the bottomadjusting screw 30 or the compression spring adjusting stem 34, or both.This setting would ordinarily be made before the cleaner leaves thefactory and based on a predetermined nozzle height of say, ft; of aninch as measured between the front lip of the nozzle mouth and thesurface of the carpet nap. And this setting once made would ordinarilybe permanent whereupon the 'cleaner should respond to variations inquality and texture of the ordinary-range of carpets to be cleaned.

Thus, the characteristic features of the adjusting mechanism hereindisclosed is the utilization of pairs of adjustable wheels, one pairbeing relatively more responsiveor susceptible to variations in thequality and texture of the carpet than the other, and of the latterwhich in turn determines the height of the nozzle. Needless to say, thesame principles may be incorporated in other and even simpler forms, oneof which has been disclosed'in Figures 7 and 8.

In the modified disclosure of the adjusting mechanism, the wheels,constitutingeach set are located at the forward end of the cleaner asbefore, butare positioned one behind the other rather than side by side.Moreover, foremost wheels 40, 40 are relatively wider and constitute theprimary Wheels, while 4| are the auxiliary wheels. wheels 40 isjournalled at the lower end of a short lever 42 pivotally mountedintermediate its ends at the lower .extremity of a vertical arm 43formed integral with a. bracket 44 suitably fastened to the underside ofthe cleaner casing. Each of the auxiliary wheels 4| is similarlyjouralso having pivotal connection with the arm 43 just above the pivotpoint of the le r 42 and extending downwardly and rearwandly therefrom.Bearing against the levers 42 and 45 adjacent their outer ends arecompression springs 46 and 41 respectively with their other ends seatingagainst abutments formed by the bracket 44.

The rearmost wheels 4|, 4| correspond to .the auxiliary wheels H of theprevious disclosure and therefore, the compression springs 41, 41 areheavy enough to counterbalance the greater part of the static load,while the springs 43 are somewhat lighter and act primarily to resistthe displacement of the front wheels under load. And finally, the levers42 and 45 are interconnected by a simple cam arrangement consisting of apin 48 projecting from the face of the longer lever 45 and bear gagainst a cam finger 42a at the upper end of the lever 42.

Thus, as the rear wheels 4|, 4| sink into the carpet nap under operatingload, the depth of penetration is reflected inthe slightlswingingmovement of their supporting levers 45, which is transmitted to thelevers 42, a direction to depress the forward wheels and thus act in thesame manner as the wheels l0,

Each of the primary the greater the depth of.

acting to adjust the position the rear wheels 4|,

shifting them in If) in the previous disclosure to raise orlower thenozzle and thus compensate for the varia- 7 tion in the thickness andtexture ofthe carpet.

ing on said auxiliary wheel supporting brackets to oppose yieldingly tothe displacement of said auxiliary wheels under the weight of-thecleaner 1 body, said primary wheel supporting bracket having a cammember bearing on said spring-pressed lever, whereby the increased depthof penetration of said auxiliary wheels under full operating loadcondition of said cleaner by virtue of their decreased width, effects aproportional displacement of said primary supporting wheel to adjustautomatically the height of said nozzle to the particular carpet surfacebeing cleaned.

arranged substantially in axial alignment-therewith, brackets pivotallymounted on said body and carrying said auxiliary-wheels, springs actingon said auxiliary wheel supporting brackets to counterbalance apredetermined portion of the weight of the cleaner body, a levershiftable with the displacement of each of said auxiliary supportingbrackets caused by the depression of said auxiliary wheels into thecarpet surface under the operating load-of. said cleaner, and a cammember on each of said front wheel supporting brackets and contactingsaid lever to effect a corresponding vertical displacement of saidprimary supporting wheels/and adjust automatically theheight of thenozzle to the depth of penetration of said auxiliary wheels into thesurface of the carpet to be cleaned.

2. A' suction cleaner comprising a body having a nozzle at its forwardend and pairs of front and rear supporting wheels, 'the front wheels 3.A suction cleaner comprising a body having a nozzle at its forward endand pairs of front and rear supporting wheels, the front wheelsconsisting of pairs of associated primary and auxi1iary wheels havingrelatively wide and narrow tread surfaces respectively, frames mountedon said body, pairs of brackets pivotally mounted side by side on saidframes and having horizontally extending arms carrying said wheels attheir forward ends, spring-pressed levers carried by said frames andacting on said auxiliary wheel supporting brackets to oppose yieldinglyto the displacement of said auxiliary wheels under the weight of thecleaner body, said primary wheel supporting brackets having cam membersbearing on said spring-pressed levers, whereby the, increased depth ofpenetration of said auxiliary wheels under full operating load conditionof said cleaner by virtue of their decreased consisting of pairs ofassociated primary and auxiliary wheels having relatively wide andnarrow tread surfaces respectively, and arranged side by side insubstantially axial alignment, brackets pivotally mounted on said bodyand having horizontally extending arms carrying said wheels at theirends, spring-pressed levers actwidth and'the increased length of thelever arms of their supporting brackets, effects a proportionaldisplacement of said primary supporting wheel to adjust automaticallythe height of said nozzle to the particular carpet surface beingcleaned.

CHARLES H. TAYLOR.

